The present invention relates generally to electronics cooling, and more particularly to cooling duct contours.
Electronic components are typically rated for a known maximum temperature. An electronic component may suffer damage or rapid deterioration above this rated temperature. Electronics are commonly cooled below rated temperatures to avoid loss of component lifetime. Components with limited thermal output or situated in cool environments may be cooled by passive convection or conduction to a cold plate or cooled structure. Hotter components and components situated in relatively hot environments benefit from active cooling.
Direct air cooling is commonly used to dissipate heat from electronics modules such as transformers and inductors. Airflow from a fan or bleed is directed onto and around the electronics module for convective cooling, with faster airflow dissipating heat more efficiently. Electronics modules are commonly cooled by unconstrained direct blast air flow from a fan outlet or situated in cooling ducts that channel airflow towards and across surfaces of the electronics modules. Most cooling ducts are substantially uncontoured tubes of rectangular or circular cross-section. Direct air cooling is often supplemented by passive cooling such as with heat pipes and/or by direct conduction.
The fluid power expended to drive direct air cooling airflow through a cooling duct or system isPower=(vF)(ΔP)  [Equation 1]where vF is volumetric airflow and ΔP is the pressure drop in the airflow direction. Larger pressure drops across the cooling duct thus cost more power. This power may for instance be provided by a larger or faster fan, or by increased bleed from a separate air system (e.g. a gas turbine engine compressor). Conventional uncontoured ducts often meet component cooling requirements by supplying high flow rates at high velocities, with large resulting pressure drops. The high fan head and volumetric flow result in increased power costs that are inefficient for many applications.